Double wall blow molded articles, such as carrying cases, have been known for decades. Such articles provide a useful combination of desirable properties, such as having high strength and relatively light weight, at a modest cost. It has also long been known to provide retaining features in or on such double wall blow molded articles in order to retain accessories, such as handles or the like, on or in the article. However, while the art of blow molded articles, including blow molded articles provided with retaining features, is well developed, deficiencies still exist.
One of such deficiencies relates to the manner in which accessories which are not an integral part of the blow molded article are retained thereby. While numerous such retaining features are known, they suffer from a number of disadvantages, such as being complex, and therefore expensive to produce and/or difficult to mold, and/or not being strong enough to support the blow molded article (particularly when the blow molded article comprises a case in which heavy objects are carried).
Another deficiency of known retaining features relates to the method in which they are created. Typically, retaining features for accessories which are not an integral part of the blow molded article require that various secondary operations be performed after the article is blow molded. Examples of such secondary operations include drilling, punching, etc. A disadvantage of requiring such secondary features is that they add to the complexity and cost of manufacturing the blow-molded article.
What is desired, therefore, is a blow molded article which includes a retaining feature which is simple and inexpensive to produce, which provides a relatively high strength connection between the blow molded article and the accessory, such as a handle, and which is formed during the molding process, without the need for secondary operations.